In a manufacturing process of a semiconductor device, a photolithography process is performed in order to form a pattern on a semiconductor wafer (a “wafer”). Various processes are performed in the photolithography process such as, e.g., a resist coating process for the wafer, an exposure process of exposing the wafer by using an exposure mask after the resist coating process, and a developing process of developing the wafer after the exposure process.
The photolithography process in the semiconductor manufacturing process is performed in a resist pattern forming system connected to an automatic transportation system of a carrier in a factory. One or more wafer lots each including a plurality of sheets of wafers of the same type are stored in the carrier. The resist pattern forming system is configured by connecting a coating/developing apparatus with an exposure apparatus in series. Wafer W that is carried out from the carrier is sequentially delivered to the coating/developing apparatus, the exposure apparatus, and the coating/developing apparatus to be processed and a series of photolithography processes are performed with respect to wafer W.
However, in the resist pattern forming system, when a system of a transportation destination of the carrier is determined, the coating apparatus, the developing apparatus, and the exposure apparatus that are to be used are automatically determined. Accordingly, when any one of the coating, developing, and exposure apparatuses is defective or the processing of wafer W is delayed, other apparatuses are influenced accordingly, thereby deteriorating the processing efficiency of the entire resist pattern forming system. In particular, since a relatively high cost is required to operate the exposure apparatus, an unnecessary cost increases when the processing efficiency is deteriorated as such, and as a result, it is inadvisable.
Japanese Patent Application No. 2007-335626, discloses a substrate processing system in which each of a coating apparatus, a developing apparatus and an exposure apparatus is constructed independently so that the carrier is sequentially transported between the respective processing apparatuses by an automatic transportation system. However, in the photolithography process, if a subsequent processing is not performed within a predetermined time after a processing operation is completed, the quality of the product may deteriorate or the subsequent processing may not be performed normally. In that case, a reproduction processing of the wafer called a rework is required and causes an additional cost.
However, in the substrate processing system, when a wafer (e.g., wafer W1) is carried into the exposure apparatus through a carrier 1 after the resist coating in the coating apparatus, an exposing process for wafer W1 may not be performed within a predetermined time after the resist is applied to wafer W1 because, e.g., another wafer (e.g., wafer W2) of a carrier 2 previously transported to the exposure apparatus may be processed in the exposure apparatus, maintenance of wafer W2 may be performed, or the apparatus may be accidentally defective. However, Japanese Patent Application Laid-Open No. 2007-335626 does not address such problems.